Specific Aim I: Through a randomized controlled trial, to measure the effects of an 18-month course of DHEA + HRT on bone mass, markers of bone turnover, and serum levels of IGF-I compared to placebo. Specific Aim II: To determine whether combined therapy with adrenal and gonadal steroid replacement changes bone structure to increase strength compared to placebo, as assessed through cross-sectional geometric analysis of DXA data.